CHAPTER XLIII. 



WEEDS : SPECIAL. 



It is not necessary or possible in a general text-book to give an 

 account of all the weeds met with in this country ; to do so would 

 be to write a flora of the British Isles, as almost any plant may 

 become a weed in localities where its favourable development 

 is secured, and occasionally plants prove troublesome which 

 are usually rare or very locally distributed. A few of the more 

 widely distributed weeds of very common occurrence on nearly 

 all farms are however sufficiently important to need special 

 mention. For more detailed descriptions of the plants the 

 student is referred to Babington's, Bentham's, or Hooker's 

 Floras of the British Isles. Although some weeds infest arable 

 ground and pasture alike, many are confined almost exclusively 

 to one or other of these two classes of land, and it is convenient 

 and useful to arrange them accordingly. 



I. Weeds of Arable Ground. 



EANUNCULACE.S.— Creeping Crowfoot {Ranunculus repens 

 L.). — A fibrous-rooted perennial " buttercup " with strong leafy 

 stolons or runners ; leaves three lobed, the segments toothed or 

 lobed also. The flower stalk is furrowed and calyx erect and 

 hairy; The fruit is a collection of achenes, each similar to 

 Fig. 226. It is introduced in seeds, especially clover and rye- 

 grass samples, and spreads rapidly by means of its runners. 



Com Crowfoot {R. arvensis L.). — An erect annual of corn 

 fields, with pale yellow flowers. The achenes are large and 



covered with hooked spines, and are often met with as an im- 



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